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Vegetation removal with fire can alter the thermal regime of the land surface, leading to significant changes in biogeochemistry (e.g. carbon cycling) and soil hydrology. In the UK, large expanses of carbon-rich upland environments are managed to encourage increased abundance of red grouse (Lagopus lagopus scotica) by rotational burning of shrub vegetation. To date, though, there has not been any consideration of whether prescribed vegetation burning on peatlands modifies the thermal regime of the soil mass in the years after fire. In this study thermal regime was monitored across 12 burned peatland soil plots over an 18-month period, with the aim of (i) quantifying thermal dynamics between burned plots of different ages (from <2 to 15 + years post burning), and (ii) developing statistical models to determine the magnitude of thermal change caused by vegetation management. Compared to plots burned 15 + years previously, plots recently burned (<2-4 years) showed higher mean, maximum and range of soil temperatures, and lower minima. Statistical models (generalised least square regression) were developed to predict daily mean and maximum soil temperature in plots burned 15 + years prior to the study. These models were then applied to predict temperatures of plots burned 2, 4 and 7 years previously, with significant deviations from predicted temperatures illustrating the magnitude of burn management effects. Temperatures measured in soil plots burned <2 years previously showed significant statistical disturbances from model predictions, reaching +6.2 °C for daily mean temperatures and +19.6 °C for daily maxima. Soil temperatures in plots burnt 7 years previously were most similar to plots burned 15 + years ago indicating the potential for soil temperatures to recover as vegetation regrows. Our findings that prescribed peatland vegetation burning alters soil thermal regime should provide an impetus for further research to understand the consequences of thermal regime change for carbon processing and release, and hydrological processes, in these peatlands., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Leaves from four different plant species (birch, willow, juniper, and heather) together with samples of the soil O and C horizons were collected at 44-46 sites along a south-to-north transect extending inland for 200 km from the southern tip of Norway. The transect covers one of the steepest vegetation gradients on Earth, crossing six vegetation zones. Juniper and heather are evergreen, and preferably exclude potentially toxic elements to avoid their accumulation in assimilating tissues, birch and willow shed their leaves in autumn together with the load of potentially toxic elements, and thus can tolerate the uptake of such elements. The plant leaves show the highest concentrations for B, Ca, K, Mg, Mn, P, Rb and S. In the soil O-horizon Ag, Au, As, Bi, Cu, Ge, Hg, In, Pb, Sb, Se, Sn, Te and W are enriched with respect to the C-horizon, whilst Mn and Rb are depleted. Cadmium, Sr and Zn are enriched in willow and Cs, Na and Tl in heather. In terms of concentration gradients from the coast inland, two different patterns are detected: 1) short range with an almost exponential decrease of concentrations from the coast, which appears to be typical for seaspray-related element input, and 2) long range with an almost linear decrease of concentrations with distance from the coast. These patterns differ among the four species, even for one and the same element. Inter-element correlation is different from material to material. Along the transect each of the different plants at the same site individually adapts to the available element combination. High linear correlations in the plants occur between the lanthanides (La, Ce, Y), and interestingly, between P and Ti. The plant/soil system appears highly non-linear and self-regulated., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Post‐mining restoration of heathland habitats has met with mixed success. Failures are often ascribed to the complexity of replicating soil conditions: a scarcity of organic matter and microbial symbionts in stored overburden used for restoration is frequently implicated. Nonetheless, systematic investigation of the role of both interventions is lacking. Using a greenhouse trial and a large‐scale field experiment within a commercial kaolinite mine site, we explored how the addition of ericoid mycorrhizal fungi (ErMF) and organic matter influenced the establishment of dwarf ericoid species that characterize NW European Atlantic lowland heaths. Neither intervention had any positive effect on ericoid establishment in field or greenhouse conditions. In the greenhouse experiment, organic matter (from commercial refuse) increased heather (Calluna vulgaris) cuttings mortality, although surviving plants showed enhanced shoot growth when ErMF were added. All field plots were dominated by combinations of grasses, gorse (Ulex europaeus), and bare ground. Establishment of ericaceous plants was remarkably low (<4%) after 3 years and Erica tetralix and C. vulgaris abundance in organic matter (which increased pH) or ErMF treatments was reduced compared to untreated control. Although our experiments suggest that research on soil manipulation treatments is required to elucidate the conditions necessary for heathland establishment, corroboration of our greenhouse trial results in field conditions highlights the value of the former in informing the latter. We identify low pH, high lignin (e.g. pine) litter as one potentially worthwhile soil amelioration treatment and suggest how the use of naturally colonized/preinoculated "nursemaid" plants could facilitate heathland restoration. [ABSTRACT FROM AUTHOR]

Prunus serotina is one of the worst invasive alien plants throughout Europe, able to rapidly replace autochthonous vegetation and form monospecific stands both in open lands and forested areas. Invasion by shrubs and trees due to abandonment of traditional management practices, is one of the major threats to the conservation of "European dry heaths", a priority habitat included in the Council Directive 92/43/EEC. The aim of this study was to assess the effects of P. serotina invasion on heathland vegetation in terms of species composition and cover, with special regards to the dominant Calluna vulgaris and Molinia arundinacea, in an area of North-Western Italy subjected to massive invasion by this alien species. We collected data on the plant cover along an invasion gradient in 10 linear transects running from P. serotina invaded stands towards non invaded ones. P. serotina differently affected the heathland vegetation. In particular, the cover of C. vulgaris and other typical heathland species such as Cytisus scoparius sharply decreased at P. serotina cover increasing. On the contrary, positive or no effect of P. serotina cover was found on M. arundinacea. Our results showed that shaded conditions created by the alien tree disfavored light demanding C. vulgaris and C. scoparius, enabling fast grower M. arundinacea to outcompete and replace them. This study emphasizes the urgency to develop management strategies to effectively control P. serotina spread in the area and to restore typical heathland species. [ABSTRACT FROM AUTHOR]

In alpine habitats, the seasonally marked climatic conditions generate seasonal and spatial differences in forage availability for herbivores. Vegetation availability and quality during the growing season are known to drive life history traits of mountain ungulates. However, little effort has been made to understand the association between plant phenology and changes in the foraging strategies of these mountain dwellers. Furthermore, this link can be affected by the seasonal presence of livestock in the same meadows. The objective of this work was to study the seasonal changes in diet composition of Pyrenean chamois (Rupicapra p. pyrenaica) and its relationship to primary production trends in a Mediterranean alpine environment. Moreover, diet composition in two populations with contrasting livestock pressure was compared in order to study the effect of sheep flocks on the feeding behaviour of chamois. From 2009 to 2012, monthly diet composition was estimated by cuticle microhistological analysis of chamois faeces collected in the eastern Pyrenees. The primary production cycle was assessed by remote sensing, using the Normalized Difference Vegetation Index. Additionally, the diet of sheep sharing seasonally the subalpine and alpine meadows with chamois was analysed. Diet selection of chamois and sheep and their overlap was also assessed. Our results show an intra-annual variation in the diet composition of Pyrenean chamois and demonstrate a strong relationship between plant consumption dynamics and phenology in alpine areas. In addition, Calluna vulgaris, Cytisus spp. and Festuca spp., as well as forbs in the summer, are found to be key forage species for Pyrenean chamois. Furthermore, this study couldn’t detect differences between both chamois populations despite the presence of sheep flocks in only one area. However, the detection of a shift in the diet of chamois in both areas after the arrival of high densities of multi-specific livestock suggest a general livestock effect. In conclusion, Pyrenean chamois are well adapted to the variations in the seasonal availability of plants in alpine habitats but could be disturbed by the seasonal presence of livestock. Due to the key plants in their diet, we suggest that population management programmes should focus on the preservation of mixed grasslands composed of patches of shrubs and herbs. The effects of climate change and shrub expansion should be studied as they may potentially affect chamois population dynamics through changes in habitat composition and temporal shifts in forage availability. [ABSTRACT FROM AUTHOR]

A primary requirement for policy objectives is reliable figures on the composition of any region. Currently there is no comprehensive, definitive set of statistics for the British Uplands, hence the present paper. An overview of the background to the region is first provided, together with some examples of the available figures and a discussion of their limitations. The paper uses a formal structure, with landscapes at the highest level followed by habitats, then vegetation, and finally species, with exact definitions of the categories applied at all levels. The figures are produced from a survey of stratified, random one kilometre squares. The tables give comprehensive figures for Great Britain (GB) as a whole, and also England, Wales and Scotland. The Uplands are shown to cover 38 % of the country. In terms of UK Broad Habitats, Bog is the most common overall (2062 k ha). It is estimated that 41 % of upland vegetation in Britain is grazed by sheep, and Cervus elephus (red deer) are particularly evident in Scotland. Walls (mainly drystone) are the most important linear feature (84 k km) but hedgerows (30 k km) are also widespread. The major vegetation classes are those linked to moorlands and bogs (about 25 %) but those associated with fertile soils are also common (10 %). In terms of species, Potentilla erecta (tormentil) is the most frequent species with four other acid grassland species in the top ten. Calluna vulgaris (ling heather) has the highest cover in Great Britain (14.8 %). [ABSTRACT FROM AUTHOR]

UK moorlands are semi-natural habitats managed for a mix of livestock, game shooting and forestry, among other activities. An assessment of the importance of characteristics that correlate with moorland bird populations of high conservation importance can inform appropriate management at appropriate locations. We use hierarchical partitioning to assess the absolute and relative importance of climate, topography, soil, landscape management (wider scale habitat configuration of forestry and agriculture) and site-based management (indices of predator control, and vegetation characteristics) in determining the abundance of a suite of upland birds in four regions of the UK. Unmeasured region-specific effects often made the largest contribution to models. Physical characteristics (climate, topography, soil) were important and on average explained a similar amount of variation to site-based management. However, there was considerable interspecific variation in the importance of both. Landscape-scale variables were generally of low importance. An index of predator control was positively correlated with the abundance of Red Grouse Lagopus lagopus scotica and two waders. Vegetation characteristics (composition and structure) were, together, strong correlates of the abundance of passerine species. Vegetation characteristics were as important as indices of predator control for waders and grouse. The importance of regional effects, physical characteristics and variables relating to management suggest targeting site-based management (such as predator control or vegetation management) to the areas where physical characteristics are most favourable. The most beneficial management will vary between species, necessitating a mosaic of management options across upland areas to benefit all species. [ABSTRACT FROM AUTHOR]

Fire behavior of plant mixtures includes a complex set of processes for which the interactive contributions of its drivers, such as plant identity and moisture, have not yet been unraveled fully. Plant flammability parameters of species mixtures can show substantial deviations of fire properties from those expected based on the component species when burnt alone; that is, there are nonadditive mixture effects. Here, we investigated how fuel moisture content affects nonadditive effects in fire behavior. We hypothesized that both the magnitude and variance of nonadditivity in flammability parameters are greater in moist than in dry fuel beds. We conducted a series of experimental burns in monocultures and 2-species mixtures with two ericaceous dwarf shrubs and two bryophyte species from temperate fire-prone heathlands. For a set of fire behavior parameters, we found that magnitude and variability of nonadditive effects are, on average, respectively 5.8 and 1.8 times larger in moist (30% MC) species mixtures compared to dry (10% MC) mixed fuel beds. In general, the moist mixtures caused negative nonadditive effects, but due to the larger variability these mixtures occasionally caused large positive nonadditive effects, while this did not occur in dry mixtures. Thus, at moister conditions, mixtures occasionally pass the moisture threshold for ignition and fire spread, which the monospecific fuel beds are unable to pass. We also show that the magnitude of nonadditivity is highly species dependent. Thus, contrary to common belief, the strong nonadditive effects in mixtures can cause higher fire occurrence at moister conditions. This new integration of surface fuel moisture and species interactions will help us to better understand fire behavior in the complexity of natural ecosystems. [ABSTRACT FROM AUTHOR]

Abstract. Over the past decades outdoor recreation has become progressively more important and as a result human‐induced potential damage has increased. In this study, short‐term effects – a 2‐yr period – of human trampling on some common forest and heath communities in Central Belgium were studied experimentally. Vulnerability to disturbance was compared among plant communities in terms of resistance, resilience and tolerance, which are based on cover measurements. The herb layer of the examined mesophilous forest communities appeared to be more sensitive than the heath and dry forest community, which were dominated by more resistant graminoid (Molinia caerulea, Deschampsiaflexuosa) and dwarf‐shrub species (Vaccinium myrtillus, Calluna vulgaris, Erica tetralix). The analysis showed that site structure and vegetation were already affected by low intensities of trampling, while vegetation recovery during the first year after trampling was limited in most plant communities. Recovery during the second year in vegetation cover as well as height was most pronounced in mesophilous forest communities. Occasional trampling clearly can lead to increased visual evidence of previous use and continued recreational disturbance. Therefore management plans should discourage hiking activity off paths and restrict recreation activities to the least vulnerable communities. [ABSTRACT FROM AUTHOR]

Calluna vulgaris (L) Hull. plants were fumigated in open-top chambers with ambient charcoal-filtered air, or 70 nl l-1 (70 ppb) ozone, for 8 h a day, five days a week. Ozone treatment during the winter increased the frost sensitivity of plants as measured by electrolyte leakage following a controlled frosting regime. Root growth was decreased and the allometric root :shoot ratio (k) was reduced by the ozone treatment, reflecting a decrease in the partitioning of carbon to the roots. There was no significant effect of ozone on instantaneous net photosynthesis. There was a significant increase in anthocyanin content in ozone-fumigated plants, but no effect on chlorophyll content. In contrast with the effects of wintertime exposure, plants treated during summer showed no significant responses. These results suggest that Calluna vulgaris can be adversely affected by prolonged ozone episodes in the field, particularly if these are followed by or coincide with frosting temperatures. [ABSTRACT FROM AUTHOR]

Short-term uptake of 137Cs by heather (Calluna vulgaris L.) was measured using radiolabelled liquid media and plants grown from shoot cuttings. Uptake by mycorrhizal plants was compared with uptake by non-mycorrhizal plants, and the effects of different external Cs and K concentrations were determined. At each time point during the 3 h experimental period the content (and hence also the apparent influx) of the mycorrhizal plants in each treatment was found to be lower than that of the non-mycorrhizal plants. An increase of 100-fold in the total external Cs concentration (from 5 to 500 μM) gave between a 35-fold and 96-fold increase in initial influx of Cs. A similar change in external K concentration, however, had little effect on Cs influx. Root-shoot transfer of Cs over the 3 h uptake period was slight; in most cases more than 90% of the radiocaesium remained in the root. The final shoot : root Cs ratio was higher in mycorrhizal than in non- mycorrhizal plants, suggesting that in mycorrhizal plants, despite their lower overall accumulation during the first 3 h, a higher proportion of the Cs taken up is translocated to the shoot. [ABSTRACT FROM AUTHOR]

Samples of Calluna vulgaris were collected from several sites of contrasting soil type and the mineral status of plants and soils measured. Differences in the concentrations of several potentially toxic elements in these plants and soils occurred but the nitrogen, potassium and phosphorus concentrations, particularly in the plants, were similar. When cuttings of Calluna from each population were grown in all soil types, it was shown that these samples were adapted to the different soils. Two ways in which this species may be adapted to tolerate high concentrations of lead were noted. [ABSTRACT FROM AUTHOR]

Rooted cuttings of heather showed their best dry matter production in drained regimes with a frequent addition of nutrients. Mycorrhizal plants generally showed a decreased production when compared with equivalent non-mycorrhizal plants, except on drained regimes low in nutrients where the mycorrhizal plants grew better. Concentrations of nitrogen in the shoot and potassium and phosphorus in the root were higher in mycorrhizal than in non-mycorrhizal plants, effects most marked in well-drained regimes with the minimum addition of nutrients. In general, alterations in nutrient and water regimes had more significant effects on dry matter production than did the presence or absence of mycorrhiza. It is concluded that mycorrhizal infection may have a beneficial effect in freely drained, infertile, soils that are characteristic of well-developed heathland. [ABSTRACT FROM AUTHOR]

Botanical composition, grazing treatment and trends in heather (Calluna vulgaris (L.) Hull.) were recorded for periods of 4-15 years at moorland sites ranging in altitude from 70 to 700 m. Tussocks of Nardus stricta L. in permanent 1-m⊃2 areas were monitored yearly at three sites. Changes in the cover of Juncus squarrosus L., Molinia eaerulea (L.) Moench and Nardus were inversely related to cover trends in Calluna, but only weakly so. Juncus squarrasus was unresponsive, with only one significant change at its twenty sites; Molinia increased significantly at four sites where Calluna declined. Nardus showed many small increases in cover which were counterbalanced by large decreases at two of its twenty-three sites, giving a negligible overall trend. Increases were largest at sheep-grazed sites, but no significant general relationship could be shown with grazing type. Nardus changes were more consistently related to. the :state of Calluna as expressed by percentage cover × height than to the trends of Calluna cover. Nardus declined once Calluna mean height exceeded 15 era. At one site heavy cattle grazing reduced Nardus cover. Many seedlings of Nardus became established, most in positions close to mature tussocks. Increment in Nardus tussock diameter was little influenced by grazing, even though tussocks grazed in one summer were more likely to be grazed in the next. It is concluded that Nardus will spread in grazed moorland unless soils are very dry or Calluna is present and allowed to grow tall for periods of several years. [ABSTRACT FROM AUTHOR]